Skip to main content

What does Task.Result really do

Cu .NET 4.5 din ce in ce mai multa lume a inceput sa foloseasca apeluri asyncrone si implictit clasa Task. In exemplul de mai jos se apeleaza un task, iar apoi se face retrive la rezulvat:
Task<string> myTask = new Task<string>( () => { ... } );
myTask.Start();
myTask.Wait();
var result = myTask.Result();
In primul rand daca avem Start, iar pe linia urmatoare avem un apel la metoda Wait, metoda Start nu mai are rost sa fie apelata. By default, cand metoda Wait este apelata, un task care inca nu este inca pornit o sa fie pornit automat de catre sistem.
In cazul in care vrem sa obtinem rezultatul, iar intre apelul de Start/Wait si Result nu avem un alt cod de executa, atunci putem sa apelam automat Result. Aceasta metoda o sa faca start automat la task si va astepta pana cand acesta se va termina si va returna rezultatul.
Codul de mai sus poate sa fie rescris in forma urmatoare:
Task<string> myTask = new Task<string>( () => { ... } );
var result = myTask.Result();
In cazul in care avem nevoie metoad Result ne permite sa setam un timeout (fiind din acest punct de vedere asemanatoare cu metoda Wait).

Comments

Popular posts from this blog

Windows Docker Containers can make WIN32 API calls, use COM and ASP.NET WebForms

After the last post , I received two interesting questions related to Docker and Windows. People were interested if we do Win32 API calls from a Docker container and if there is support for COM. WIN32 Support To test calls to WIN32 API, let’s try to populate SYSTEM_INFO class. [StructLayout(LayoutKind.Sequential)] public struct SYSTEM_INFO { public uint dwOemId; public uint dwPageSize; public uint lpMinimumApplicationAddress; public uint lpMaximumApplicationAddress; public uint dwActiveProcessorMask; public uint dwNumberOfProcessors; public uint dwProcessorType; public uint dwAllocationGranularity; public uint dwProcessorLevel; public uint dwProcessorRevision; } ... [DllImport("kernel32")] static extern void GetSystemInfo(ref SYSTEM_INFO pSI); ... SYSTEM_INFO pSI = new SYSTEM_INFO(

Azure AD and AWS Cognito side-by-side

In the last few weeks, I was involved in multiple opportunities on Microsoft Azure and Amazon, where we had to analyse AWS Cognito, Azure AD and other solutions that are available on the market. I decided to consolidate in one post all features and differences that I identified for both of them that we should need to take into account. Take into account that Azure AD is an identity and access management services well integrated with Microsoft stack. In comparison, AWS Cognito is just a user sign-up, sign-in and access control and nothing more. The focus is not on the main features, is more on small things that can make a difference when you want to decide where we want to store and manage our users.  This information might be useful in the future when we need to decide where we want to keep and manage our users.  Feature Azure AD (B2C, B2C) AWS Cognito Access token lifetime Default 1h – the value is configurable 1h – cannot be modified

ADO.NET provider with invariant name 'System.Data.SqlClient' could not be loaded

Today blog post will be started with the following error when running DB tests on the CI machine: threw exception: System.InvalidOperationException: The Entity Framework provider type 'System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer' registered in the application config file for the ADO.NET provider with invariant name 'System.Data.SqlClient' could not be loaded. Make sure that the assembly-qualified name is used and that the assembly is available to the running application. See http://go.microsoft.com/fwlink/?LinkId=260882 for more information. at System.Data.Entity.Infrastructure.DependencyResolution.ProviderServicesFactory.GetInstance(String providerTypeName, String providerInvariantName) This error happened only on the Continuous Integration machine. On the devs machines, everything has fine. The classic problem – on my machine it’s working. The CI has the following configuration: TeamCity .NET 4.51 EF 6.0.2 VS2013 It see